Lamp Base Display

In 1923 M. D. Cooper published an article¹ in the Electrical World that was titled "Simplification in the Lamp Industry." It was a time when change was necessary as far as lamp bases (and sockets) and voltages were concerned. That part of Cooper's article that deals with bases is presented here. The selection of standard voltages also had a marked effect on the reduction in the number of lamp types manufactured. Regarding standardization of bases and sockets, Cooper said:

"The average person in buying an electrical article of any kind - a receptacle, a lamp or the like - has little conception of the meaning to him of the simplification work which is embodied in that device. This simplification work may favorably affect any or all of the following attributes of the thing purchased: (1) The quality; (2) the price; (3) the adaptation to the function to be performed; (4) the ready availability of the device in quantities as desired.
"To get a realistic picture of the advantages of simplification, consider for a moment some of the steps toward simplification which have been taken in the incandescent lamp industry, and then visualize what the conditions in the electrical trade would be today if these simplifications had not been accomplished.

Fifty-Five Thousand Varieties "In the '90s there were in common use in this country fourteen different kinds of bases, with their corresponding sockets, for incandescent lamps. This number does not include the large bases used on series-burning lamps for street lighting. Incandescent lamps for general lighting service were also supplied for each individual voltage between 100 and 130. There was some demand for lamps of 200 volts and above, but for purposes of comparison with present conditions these may be neglected. Without regard to such differences in design of the lamp as shape of bulb, mounting of the filament or finish of the bulb (such as clear or frosted), there were therefore for each individual size of lamp thirty times fourteen, or 420, possible variations which had to be taken into account in manufacturing that one size of lamp.
"In the year 1900 the only kind of lamp available was the carbon-filament lamp, of which there were five standard sizes - the 2, 4, 6, 8, 16 and 32 cp. Different manufacturers used different forms of filament construction and also different sizes and shapes of bulb. For purposes of illustration, let us say that there were only four of these variations in bulb size and shape. As to bulb finish there were three variations - clear, bowl-frosted and all-frosted. Variations of bulb color can be neglected, since lamps with colored bulbs had a limited application. At the beginning of this century there were, then, four times three, or twelve, possible variations of bulb shape and finish, or twelve times 420, or 5,040, variations in each size of lamp. At least three of the five regular sizes of lamps were each made for three different efficiencies. In respect to size and efficiency there were then eleven variations, and the total number of types of lamps was eleven times 5,040, or about 55,000 - all used in the ordinary course of incandescent lighting.
"The first efforts toward simplification had for their object the standardization of the lamp base. In spite of the general opinion to the contrary, this simplification was not difficult to accomplish. The Edison screw type of base, or the medium screw as it is now called, was chosen as the type for future standardization, and by means of adapters the use of the medium-screw base in the sockets of the other principal types was made possible.The lamp manufacturers contributed very largely to the speed with which the movement was accomplished by offering a lamp with the standard base together with an adapter at the same price which was charged for the lamp carrying the base which it was desired to eliminate. Simultaneously, steps were taken which led to the standardization of the mogul-screw base for series lamps. It was but a few years until the demand for lamps with any except the standardized bases had decreased to an infinitesimal percentage of the total demand, and at the present time, twenty years after, one of the superseded types of bases or sockets is a museum exhibit rather than an article of every-day commerce. This standardization of bases decreased the number of types of lamps in common use for multiple lighting from 55,000 to one-fourteenth of that number, or 3,900."

The picture above was taken from original photograph used in Reference No. 1
Dimensions of picture in the article are about 2-1/4" by 3"
The base (and socket) display board shown in the Cooper paper was constructed by the Providence Base Works, of the General Electric Company. It has 18 columns and 10 rows of bases - minus 12 bases (where a smaller display board exists.) Therefore there were a total of 180 - 12 = 168 different lamp bases on the board. The writer had the opportunity to see the original photograph of that board as well as about two-thirds of the bases. A scanned image of the picture is shown above. With the aid of a hand magnifier and the original photograph, the tag on each base could be read and the base type determined as well. The number of bases on the board that were manufactured by different companies is tabulated below. The Edison medium screw base plus the five new bases shown on the small display board supplanted all of the bases displayed on the board. It is believed that the display bases were made about 1900.

It can be seen that about 88% of the bases displayed on the board were made by eight companies.

Some of the actual bases that were mounted on the display board are shown below.

Edison bases

Ediswan (bayonet) double contact bases

On left: Three single contact Ediswan (bayonet) bases. On right: Truitt base

Brush-Swan bases

Westinghouse bases

United States bases

Thomson-Houston bases

Base types, from left to right: Loomis, Fort Wayne Jenney, Schaefer, Perkins (or Mather)

From left, two Westinghouse Stopper bases, Mogul Heisler round pin base, Mogul Bernstein round pin base

Edison-Westinghouse combination bases

Note: The image of M. D. Cooper was taken from Reference 2.

References
1) M. D. Cooper, "Simplification in the Lamp Industry - How the 55,000 Types of Lighting Units in Existence in 1900 Have Been Reduced to 342 - Standardization of Lamp Bases and Voltages," Electrical World, Vol 82, No 12, Sep 22, 1923, pp 629-631.
2) Book of the Incas, 1928.